Histories of Plants in Medicine



  • Earilest known medical document by Sumerians
    • 4,000 years ago in Mesopotamia


  • Herbal medicines were prevalent in ancient Egypt
    • mandrake for pain, garlic for heart
    • remedies ‘published’ in Ebers Papyrus


  • Ancient Chinese reveal herbal remedies
    • Pun-tsao (1600) thousands of herbal remedies


  • Aztecs gifted Badianus manuscript to king of Spain
    • herbal remedies for 100 afflictions

Ancient Greeks are the Foundation of Western Medicine



  • Greek physician, Hippocrates, Father of Medicine
    • believed diseases had natural causes
    • used various herbal remedies
    • works used for 1500 years!


  • Dioscorides, Roman military physician, wrote ‘De Materia Medica’
    • 600 species of plants with medicinal value
    • recorded while on ‘military travel’


  • Herbal remedies by Greeks/Romans have been kept and lost
    • willow bark tea = precursor to asprin
    • Ferula used for contraception but collected to extinction

Age of Herbals: Doctrine of Signatures



  • Renaissance age (1500) & printing press created a revival of herbalism
    • 4 German ‘Fathers of Botany’
    • Gerard, “The herbal of general history of plants”


  • Publishings included medicinal uses & superstitions
    • Culpepper, “The complete herbal” included astrology


  • Doctrine of Signatures: herbs resembling various parts of the body can be used to treat ailments of those body parts
    • juice of bloodwort treats blood disorders
    • lobed liverwort treats liver complaints

Modern Prescription Drugs


  • Herbalism diminished in recent centuries, but remedies still were effective
    • remedies became ‘prescriptions’ by physicians
    • William Withering, 1775, foxglove for heart failure
    • new standard for pharmaceutical industry


  • Purifying active extracts started in 19th century
    • morphine from poppy in 1806
    • synthetic drugs based on natural products ~1850s


  • Salicyclic acid (many plants) synthesized for pain relief
    • led to development of aspirin


  • 25% of prescriptions today contain plant-derived active ingredients
    • research still investigating new active compounds
    • e.g. studying ingredients in Native America remedies

Herbal Medicine Today


  • Rural populations still rely on herbal medicine
    • China, India, S. America & Africa
    • projected to reach $1.3 Billion by 2023


  • Modern Chinese medicine combines herbal, acupuncture & Western medicine
    • unique health care from 1 billion people
    • thousands of medicinal herbs


  • Modern Indian culture believe in traditional medicine
    • manufactured pharmaceuticals too expensive
    • reliance on indigenous cures


  • Rainforests are hubs of medical potential, but are decreasing
    • loss of tribal herbal practices

Active Principals in Plants





  • Medicine value tied to chemical compounds
    • manufactured by biochemical pathways


  • Compounds called ‘secondary products’ as they do not directly impact metabolism
    • alkaloids, glycosides, terpenes & phenolics


  • Herbivore defense, inhibit fungal or bacteria pathogens

Alkaloids and Glycosides



  • Alkaloids: diverse compounds found in dicots
    • contain nitrogen
    • bitter
    • impact animal nervous systems
    • medicinal, poisonous, hallucinogenic
    • caffeine, nicotine, cocaine, morphine, quinine


  • Glycosides: widespread compounds with glucose
    • cyanogenic or cardioactive glycosides, saponins
    • steroid molecules as active component
    • treat heart failure
    • precursors for sex hormones
    • can be very toxic

Medicinal Plants: Foxglove



  • Foxglove (digitalis purpurea) bienneial in snapdragon family
    • lawn ornamental
    • 30 different glycosides
    • can be very toxic


  • Millions of USA heart patients rely on digitalis as primary treatment


  • In 1775, British physician learned of a folk remedy for dropsy
    • bloating due to fluid accumulation: congestive heart failure
    • digitalis tea became treatment
    • slows heart rate, increase strength of heartbeat

Medicinal Plants: Willow to Aspirin



  • Willow tree bark used for pain reduction in many cultures
    • ancient Greeks and Native Americans
    • reduces fever and chills


  • Evolution of aspirin began with willow bark experiments in England
    • 1828, salicin isolated as active ingredient
    • salicin derivatives occur in many species


  • BAYER focused on acetylsalicylic acid from Spirea plant
    • less digestive issues
    • renamed to aspirin

Medicinal Plants: Fever Bark Tree



  • Malaria is one of the worlds most prevalent diseases
    • 200 million infections each year
    • records of malaria date back to ancient Egyptians
    • female Anopheles mosquite w/ Plasmodium parasite


  • Fever bark tree was first treatment for malaria
    • native to east slopes of Andes mtns
    • belongs to coffee family
    • used by Incas to treat fever, then malaria


  • Trade developed for powdered bark
    • 2lbs to treat one person
    • quinine was isolated before over-exploitation
    • now: synthetic cholroquinine

Medicinal Plants: Ephedra


  • Ephedrine is a plant alkaloid produced by genu Ephedra
    • only one genus in the family of gymnosperms
    • native to Americas, Europe, Asia & Africa


  • Long cultural history as a herbal medicine
    • decongestant and respiratory ailments


  • Ephedrine still found in modern drugs
    • relaxes bronchial muscles
    • CNS stimulant


  • Large scale abuse of herbal Ephedra products
    • herbal ecstasy, similar to amphetamines
    • activates thermogenesis, calorie burning
    • supplements illegal, medications ?

Medicinal Plants and Cancer



  • Humans have suffered cancer for 1,000s of years
    • Ebers Papyrus suggested treatments
    • 2nd leading cause of death in US


  • Plants have always featured in folk remedies
    • search for anticancer plant sources began in 50’s by NCI
    • 1,000s of plants have been screened
    • several now part of chemotherapy treatments


  • Vinca alkaloids for leukemia (Madagascar periwinkle)
  • Taxol from Pacific yew used in many chemotherapy treatments
  • Camptotheca from Chinese happy tree for ovarian cancer

Herbal Remedies: Promises and Problems



  • Plants and plant extracts feature prominently in alternative medicines
    • considered dietary supplements by FDA
    • $7 billion a year industry


  • Dietary supplements are not subject to FDA approval
    • no rigorous clinical testing
    • FDA will only take reactionary actions


  • Secondary plant compounds may have health benefits or cause adverse reactions
    • 40% of US populations uses alternative medicines
    • no clinical linkage to medications